It is, of course. Apologies for that; you could disconnect the outside sensor and connect a resistor with a relay operated by the DHW thermostat. An electronic solution would be more elegant, but more £££.
2 condensing boilers
- Thread starter ajrobb
- Start date
It is, of course. Apologies for that; you could disconnect the outside sensor and connect a resistor with a relay operated by the DHW thermostat. An electronic solution would be more elegant, but more £££.
Sponsored Links
JUst out of curiosity, how hard is it to actually build a WC?
Not hard at all!
You could even do it with virtually just passive components.
A very simple way to convert an old boiler like an Ariston, Biasi, Chaufateux, Halstead............ is just to use an external NTC and a single transistor or an op-amp and then power an LED to illuminate a photoresistor which controls the current in the mod coil.
Its the simplest thing in the world as a basic controller.
Tony
You could even do it with virtually just passive components.
A very simple way to convert an old boiler like an Ariston, Biasi, Chaufateux, Halstead............ is just to use an external NTC and a single transistor or an op-amp and then power an LED to illuminate a photoresistor which controls the current in the mod coil.
Its the simplest thing in the world as a basic controller.
Tony
Cheers Tony, really interested in this. Do you have an electrical diagram at all? What's an ntc? Where/how does the diy wc connect to the system?
Cheers pal
Cheers pal
Sponsored Links
Just read it properly, by mod coil I assume you mean the gas valve burner solenoid?
You know what I mean matey, just making sure were talkin bout the same part. What's the wiring sequence as you say?
I wasn't correcting you
I wasn't correcting you
I'm not thinking for mine, just interested in how it's done.
L
Lochy
Here you go mate, try this;
http://www.redcircuits.com//Page46.htm
I wish I had the time to go into electronics more deeply & I respect the knowledge the guys like Tony have. Tony Agile posts are always worth a read.
L
Lochy
Can you please post up a rough schematic Tony?
Sorry I dont have the computer drafting skills to draw a circuit as well as little time at present.
In any case its not relevant when the manufacturers now have their own ( expensive ) WC units. It also constitutes a non manufacturer approved modification.
That circuit linked to above is only a thermostat. It does not modulate the boiler flow temperature which is the basis of current W/C which aims to ensure a boiler condenses as much as possible. Its only an on/off switched thermostat.
In fact I dont see much point of it as only the internal temperature needs to be monitored for comfort. The advantage of WC is to reduce the flow temperature when possible to give greater boiler efficiency.
Tony
In any case its not relevant when the manufacturers now have their own ( expensive ) WC units. It also constitutes a non manufacturer approved modification.
That circuit linked to above is only a thermostat. It does not modulate the boiler flow temperature which is the basis of current W/C which aims to ensure a boiler condenses as much as possible. Its only an on/off switched thermostat.
In fact I dont see much point of it as only the internal temperature needs to be monitored for comfort. The advantage of WC is to reduce the flow temperature when possible to give greater boiler efficiency.
Tony
I looked up the boiler brochure and I&M manuals on-line. The brochure says the boiler is compatible with most external controllers, but the manual doesn't say how this is done. There are a pair of terminals (SL) that are linked, so I'd think they are probably an optional connector for an external controller; you'd need to check with Keston as to how a controller is connected.
The boiler pump is a standard 3-speed Grundfos, but it has a 5-core connector and the pump speed is altered by the boiler's controller to control the differential temperature.
The single boiler low-loss header recommended by Keston is a length of 1 1/2" pipe connecting F to R, with the secondary tees at either end.
http://www.keston.co.uk/downloads/support_info/multiple/1xblr-h.pdf
I'd think the boiler's hydraulic resistance is enough to allow the pump to operate properly without any additional resistance from the system. I know pumps generally don't like operating against a very low resistance.
The DRVs mentioned above may not be necessary.
The boiler pump is a standard 3-speed Grundfos, but it has a 5-core connector and the pump speed is altered by the boiler's controller to control the differential temperature.
The single boiler low-loss header recommended by Keston is a length of 1 1/2" pipe connecting F to R, with the secondary tees at either end.
http://www.keston.co.uk/downloads/support_info/multiple/1xblr-h.pdf
I'd think the boiler's hydraulic resistance is enough to allow the pump to operate properly without any additional resistance from the system. I know pumps generally don't like operating against a very low resistance.
The DRVs mentioned above may not be necessary.
Heres a pic of the last one i did if your interested.
Cheers mate, yeah did the whole installation. Was a 70k job for Arnold Clarke. Well spotted on the oxy kit lol. Few other pics knocking round somewhere too.
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
Sponsored Links
